Pirates Acquire J.A. Happ

The Pirates announced that they’ve acquired left-hander J.A. Happ from the Mariners in exchange for minor league righty Adrian Sampson.

In picking up Happ, the Pirates have struck a last-minute deal to add a back-of-the-rotation starter to their ranks. The 32-year-old pitched to solid results for much of his first and only season with the Mariners, but he’s run into trouble as of late, posting an unsightly 8.47 ERA over his past four starts — a span of just 17 innings. At his best, Happ is a serviceable back-of-the-rotation arm whose greatest problem is a susceptibility to home runs versus right-handed hitters. PNC Park’s dimensions will help to mitigate that concern, as it’s ranked as one of the toughest parks in terms of right-handed home run factor in each of the past three full seasons.

On the year, Happ has a 4.64 ERA with 6.8 K/9, 2.7 BB/9 and a 42.1 percent ground-ball rate in 108 2/3 innings. Those numbers are more or less in line with the totals he delivered from 2012-14, although they came in the hitter-friendly Rogers Centre as opposed to the pitchers’ paradise that is Safeco Field. (His ERA+ from ’12-’14 was 89, compared to just 80 this season.) Happ is earning $6.7MM this season and is a free agent this winter, so he’ll be a short-term pick up that the Pirates can use as rotation insurance down the stretch.

The 23-year-old Sampson ranked as the Pirates’ No. 28 prospect on MLB.com’s midseason update, where Jim Callis and Jonathan Mayo praise the righty’s sinking fastball and ability to get grounders. The MLB.com duo notes that Sampson has strong command and average stuff across the board, giving him a low ceiling but also placing him close to big league ready. Sampson has started 21 games at Triple-A Indianapolis this season and has a 3.98 ERA with 6.9 K/9 and 2.1 BB/9 in 124 1/3 innings in that time.